1. Field of the Invention
This invention relates in general to electrical switches, particularly those associated with battery operated devices.
2. Statement of the Problem
As electronic circuitry has shrunk in size, a number of inventors have attempted to develop or improve systems for providing smaller and more compact battery supplies and switches for portable electrical devices. Space is at a premium in these devices and, because switches and replaceable batteries both need to be accessible by the user, these pose a physical limit to reducing the size of the device. One approach to solving the compactness issue employs miniature diaphragm momentary contact switches in lieu of bulkier slide, rotary, pushbutton or toggles switches. This method reduces the physical size of the switch and provides additional utility by allowing multiple actuations of a single switch to control various operating modes of the device. However, the user still requires direct access to the switch, and the switch itself consumes valuable area on both the circuit board and exterior surface of the device.
Another approach replaces one of the battery contacts with an intermediate coil or leaf spring which prevents the battery contact from closing a circuit until sufficient pressure is supplied by means of a sliding or screw driven actuator. Although this method eliminates a traditional switch as a separate component, the actuator mechanism doesn't reduce the weight, bulk, or complexity of the device. In addition, this system is not suitable for reliably producing discrete momentary contact pulses required for modal control of integrated circuitry.
None of the prior art approaches are able to combine both compactness and the ability to access the battery and switch. If such a switch and battery assembly were available, it would make possible a whole new spectrum of miniaturized portable battery-operated devices.